Research of Full Digital DC/DC Converter Based on DSP

Research on the Control of Switch Power Supply Based on the Digital Potentiometers

“…G c (S) stands for the transfer function of the control section, G PWM (S) stands for the transfer function of the PWM generate section, G LC (S) stands for the transfer function of the filter section, and G FB (S) stands for the transfer function of the feedback section. After through the feedback section, which is usually voltage sampling network, the output voltage U o is transferred into U FB , and compared with the reference voltage U ref , their difference as the input of the control section, which is usually a PID controller [1] [2] . By comparing the PID controller's output with carrier in the PWM generate section, the duty cycle D can be got, thus, the output voltage is decided.…”

“…By using SCM as the controller, it can easily grasp the design method, and the demand to the SCM is low, also it is low cost [1] , however, the control circuit could be very complicated, and certain delays are exist, which may affect the dynamic performance and precision of the Switch power supply. When using high quality DSP and FPGA digital chip as the controller, the design of the control circuit can be simplified, and various complicated algorithms can be implemented quickly and efficiently because of the chips' high sampling speed and calculating speed [2] [3] , but the chips' complicated architectures, high cost and difficult control technologies limit their development. Meanwhile, by the developing of the power chips, the design of those constant output switch power supplies become very easy, the control is usually accomplished through analog circuits, which makes the response of the circuits very fast [4] [5] .…”